With the development of IP-based networks, traditional telecom services need to be transferred towards IP-based next-generation networks. At present, standards organizations such as 3rd Generation Partnership Project (3GPP), 3rd Generation Partnership Project 2 (3GPP2) and Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN) all regard Session Initiation Protocol (SIP) as a basic protocol of a next-generation core network and consider an SIP-based IP network as a network foundation of service applications. A converged service system is a new system architecture based on a next-generation network. In a converged service system, various networks with different structures coexist and can be interconnected and realize seamless connection and handover, wherein realizing a group session through an SIP-based network is one of the main functions of a converged service system.
An SIP-based converged service system supports not only a message exchange between converged service users but also a message exchange between a converged service user and a traditional message service user. During a message exchange between a traditional message service user and a converged service user, when the traditional message service user sends a message to the converged service user and requires a return receipt or a reading report from the converged service user, the diversity of traditional message service systems makes the return receipt or reading report from a converged service system unable to be correctly sent to the corresponding traditional message service system, resulting in the traditional message service user unable to correctly receive the return receipt or reading report from the converged service user and going against the service experience of the user.